【思特奇杯·云上蓝桥-算法训练营】第十一届蓝桥杯大赛第二场省赛试题C&C++ 大学B组真题

结营考核

文章目录

• ​​A.门牌制作​​
• ​​B.既约分数​​
• ​​C.蛇形填数​​
• ​​D.跑步锻炼​​
• ​​E.七段码​​
• ​​F.成绩统计​​
• ​​G.回文日期​​
• ​​H.字串分值和​​
• ​​I.平面切分​​
• ​​J.字串排序​​

A.门牌制作

代码：

num = 0
for i in range(1, 2021):
    i = str(i)
    num += i.count('2')
print(num)

答案： 624

B.既约分数

代码：

num = 0
# 辗转相除
def func(a, b):
    x = a % b
    while x != 0:
        a = b
        b = x
        x = a % b
    return b

for i in range(1, 2021):
    for j in range(1, 2021):
        if func(i, j) == 1:
            num += 1
print(num)

答案：2481215

C.蛇形填数

代码：

dir = 0  # 0代表向右，1代表向下
a = [[0 for i in range(100)] for j in range(100)]
x, y = 0, 0
num = 1
while True:
    if x == 19 and y == 19:
        break
    while dir == 0:
        x, y = x, y+1
        num += 1
        while y != 0:
            x += 1
            y -= 1
            num += 1
            if x == 19 and y == 19:
                print(num)
                break
        dir = 1
    while dir == 1:
        x, y = x+1, y
        num += 1
        while x != 0:
            x -= 1
            y += 1
            num += 1
            if x == 19 and y == 19:
                print(num)
                break
        dir = 0

答案： 761

D.跑步锻炼

代码：

year = 2000
month = 1
day = 1
week = 6
res = 0
dateday = [0,31,28,31,30,31,30,31,31,30,31,30,31]

# 闰年判断
def run(year):
        if year % 4 == 0 and year % 100 != 0:
                return True
        elif year % 400 == 0:
                return True
        else:
                return False

while year != 2020 or month != 10 or day != 1:
        if run(year):
                dateday[2] = 29
        else:
                dateday[2] = 28
        day += 1

        week = (week+1)%7

        if day > dateday[month]:
                day = 1
                month += 1
        if month > 12:
                month = 1
                year += 1
        if day == 1 or week == 1:
                res += 1
        res += 1
res += 2
print(res)

答案： 8879

E.七段码

代码：

这个可以数发光的个数：
1 ： 7种
2： 10种
3： 16种
4： 20种
5： 19种
6： 7种
7： 1种
ans = 7 + 10 + 16 + 20 + 19 + 7 + 1 = 80
一共80种

F.成绩统计

代码：

n = int(input())
num1 = 0
num2 = 0
for i in range(n):
    stu = int(input())
    if stu >= 60:
        num1 += 1
    if stu >= 85:
        num2 += 1
print('{:d}%'.format(round(num1/n*100)))
print('{:d}%'.format(round(num2/n*100)))

G.回文日期

代码：

from calendar import isleap
n = int(input())

def check(year):
    month = int(year[:2])
    day = int(year[2:4])
    year = int(year)
    if 1 <= month <= 12:
        if month == 2:
            if isleap(year):
                if day <= 29:
                    return True
                else:
                    return False
            else:
                if day <= 28:
                    return True
                else:
                    return False
        if month in [1,3,5,7,8,10,12]:
            if day <= 31:
                return True
            else:
                return False
        else:
            if day <= 30:
                return True
            return False
    return False
arr1 = []
arr2 = []
for i in range(1000, 9999):
    x1 = str(i)[::-1]
    x2 = (str(i)[:2]+str(i)[:2])[::-1]
    if check(x1) and int(x1[::-1]+x1)>n:
        arr1.append(int(x1[::-1]+x1))
    if check(x2) and int(x2[::-1]+x2)>n:
        arr2.append(int(x2[::-1]+x2))

print(arr1[0])
print(arr2[0])

H.字串分值和

代码：
暴力解法肯定不能ac，大概50%是可以过的

s = input()
n = len(s)
res = 0
left = 0
right = 0
while left < n:
    if right == n:
        left += 1
        right = left
    right += 1
    s_ = set(s[left:right])
    res += len(s_)
print(res)

I.平面切分

代码：

n = int(input())
li = []
for i in range(n):
    li.append(list(map(int, input().split())))
res = 2 
node = []
for i in range(1, n):
    for j in range(i):
      if li[i][0] != li[j][0]:
        x = (li[i][1] - li[j][1]) / (li[j][0] - li[i][0])
        y = li[j][0] * x + li[j][1] 
        if [x, y] in node:
            pass
        else:
            node.append([x, y]) 
    res += len(node) + 1
    node = []
print(res)

J.字串排序

#include <cstring>
#include <iostream>
#include <algorithm>

using namespace std;

const int N = 135, M = 10010;

int f[N][30][N];
//chcnt[i][j]记录第i个位置取字母j+'a'的逆序对最大值 
int chcnt[N][30];
//mlen[i]记录每个位置的最大值 
int mlen[N];

void dp()
{
    for (int i = 2; i < N; ++i)
    {
        int m = 0;
        for (int j = 1; j <= 'z' - 'a'; ++j)
        {
            for (int k = 1; k < i; ++k)
            {
                if (k > 1) f[i][j][k] = f[i - 1][j][k - 1] + i - k;
                else f[i][j][k] = chcnt[i - 1][j - 1] + i - 1;
                chcnt[i][j] = max(chcnt[i][j], f[i][j][k]);
            }
            m = max(m, chcnt[i][j]);
        }
        mlen[i] = m;
    }

}

int main()
{
    dp();

    int score = 0;
    cin >> score;
    //找出最短长度值
    int beg = 0;
    for (int i = 1; i < N; ++i)
        if (mlen[i] >= score)
        {
            beg = i;
            break;
        }

    int curr = 0;   //用于记录逆序值
    int same = 1;   //记录后缀中有多少个相同字母
    char last = 'z' + 1;//记录上一个字母是什么 
    for (int i = beg; i > 0; --i)
    {
        //从a开始枚举
        int j = 0;
        for (; j <= last - 'a'; ++j)
        {
            if (j == last - 'a') curr -= same;
            if (curr + chcnt[i][j] >= score)
            {
                curr += i - 1;
                break;
            }
        }
        if (j == last - 'a') same++;
        else
        {
            last = j + 'a';
            same = 1;
        }
        cout << last;
    }
    cout << endl;

    return 0;
}